Spectacle lens design, method of manufacturing a spectacle lens and method of providing a spectacle lens for at least retarding myopia progression

This application is a continuation application of international patent application PCT/EP2021/083248, filed on Nov. 26, 2021 and designating the U.S., which claims priority to European patent application EP 20 211 639.8, filed on Nov. 26, 2020, both of which are hereby incorporated by reference in their entireties.

The present disclosure relates to a spectacle lens design for a spectacle lens, in particular for a single vision spectacle lens, to be positioned relative to the eye of a wearer according to a given as-worn position and to a method of manufacturing such a spectacle lens. In addition, the disclosure relates to method of providing a spectacle lens for at least retarding myopia progression based on measured eye-data.

The prevalence of myopia (short sightedness) is increasing rapidly. Myopia significantly increases the risk of retinal detachment, (depending on the level of myopia), posterior cataract and glaucoma. The optical, visual and potential pathological effects of myopia and its consequent inconvenience and cost to the individual and community, makes it desirable to have effective strategies to slow the progress, or prevent or delay the onset of myopia, or limit the amount of myopia occurring in both children and young adults.

WO 2005/055891 A1 and WO 2007/092853 A2, however, disclose that peripheral retinal image (i.e., peripheral vision) plays a major role in determining overall eye length, and is an effective stimulus that promotes peripheral and total eye growth that results in axial elongation, an overall increase in eye size and myopia.

In a key experiment described in WO 2005/055891 A1, primates were reared with annular diffusing lenses placed in front of the eye. The annular diffusing lenses allowed light rays from on axis, central field objects to reach the eye unobstructed. The same annular diffusing lenses scattered or diffused light rays from off-axis, peripheral field objects. This scattering induced form deprivation only to off-axis visual objects in the peripheral field, while maintaining clear vision for the central field. It is known to vision scientist working on myopia development that form deprivation applied to the entire visual field (or central field) of the eye induces axial growth leading to myopia. In the experiment disclosed in WO 2005/055891 A1, involving form deprivation to only the peripheral field, the eye also developed myopia due to axial elongation and eye growth.

In an extension to the experiment described in WO 2005/055891 A1, the annular diffusing lenses were removed from some eyes following development of substantial amounts of myopia. When the annular diffusing lenses were removed, the amount of myopia in the primates decreased.

Further, in a parallel extension to the experiment, for other eyes, in addition to removal of the annular diffusing lenses following development of substantial amounts of myopia, central vision of the primate's eye was eliminated, by using an Argon (blue-green) laser to ablate the macular portion of the retina by photocoagulation, essentially blinding central vision while sparing peripheral vision. Even when on-axis central, foveal vision was interrupted in this manner, the decrease in myopia remained similar to when central vision was not disrupted. Based on learning from these experiments that demonstrate that the peripheral retinal image (i.e., peripheral vision) plays a major role in determining overall eye length, and is an effective stimulus that promotes peripheral and total eye growth that results in axial elongation, an overall increase in eye size and myopia, WO 2005/055891 A1 discloses a method of abating, retarding or eliminating the progression of myopia in an individual by controlling off-axis aberrations through manipulating the curvature of field of a visual image in a predetermined fashion and ultimately altering, reducing or eliminating eye axial elongation. In this method by which myopia progression may be retarded (and in many cases, halted or reversed) an optical device having a predetermined off-axis aberration-controlled design that abates, retards or eliminates eye growth while simultaneously providing clear central imaging is used.

The authors of WO 2005/055891 A1 describe a method and apparatus for controlling optical aberrations to alter relative curvature of field by providing ocular apparatuses, systems and methods comprising a predetermined corrective factor to produce at least one substantially corrective stimulus for repositioning peripheral, off-axis, focal points relative to the central, on-axis or axial focal point while maintaining the positioning of the central, on-axis or axial focal point on the retina. The method and apparatuses are used to provide continuous, useful clear visual images while simultaneously retarding or abating the progression of myopia.

The authors propose e.g., an optical device, such as spectacles, contact lenses, artificial corneal devices such as on-lays and in-lays, corneal implants, anterior chamber lenses or intraocular lenses, or employing interventions, such as methods for corneal and epithelial remodeling and sculpting including orthokeratology and refractive surgery such as epikeratophakia, thermokeratoplasty, LASIK, LASEK, and PRK that can provide a resultant negative relative curvature of field at the retina, and that in addition, in order to continue to provide good central visual acuity for critical visual tasks, the optical device or optical intervention should ensure good focus of central field image to the retina.

The documents WO 2005/055891 A1 and WO 2007/092853 A2 disclose a suitable spectacle lens. This spectacle lens is designed such that it would generate a negative relative curvature of field on the eye. According to the authors this arrangement is advantageous over conventional under-correction approaches as the central, on-axis image point is focused sharply to the fovea enabling good visual acuity. The peripheral image points, due to the negative relative curvature of field, are focused more anteriorly, or in front (i.e., in the direction against the direction of light in the eye) of the retina. This has the effect of producing a relative under-correction to the peripheral field, which, from the experiment results, would control eye growth and axial elongation. That is, due to the more anterior location of the off-axis, peripheral field image points, stimulus to axial growth is significantly reduced, eliminated or reversed in the eye, leading to reduction or elimination of myopia development or reduction and even reversal of myopia progression.

The first versions of spectacle lenses following this approach are developed by the Carl Zeiss Vision group in cooperation with the Brian Holden Vision Institute. One of the first spectacle lens designs following this approach is e.g., disclosed in WO 2007/041796 A1.

Another spectacle lens design being launched under the trademark Myovision is e.g., disclosed in WO 2009/052570 A1.

According to Prof. Schäffel in a presentation entitled “Individualisierte Myopiebehandlung bei Kindern [Individualized myopia treatment in children]” by Prof. Dr. Frank Schaeffel and Dr. Hakan Kaymak (Innovationssymposium 2019)” held on Jan. 19, 2019 in Dusseldorf, Germany, Essilor markets a similar design under the trademark Myopilux.

Further lens designs following the theory described in WO 2005/055891 A1 are disclosed in WO 2009/129528 A1 assigned inter alia to Novartis AG. These lens designs being characterized by a peripheral optical zone surrounding a central zone. Said peripheral zone includes an incident angle with respect to the optical axis of about 30 degrees and has a positive peripheral refractive power relative to the refractive power of the central zone of that lens to thereby provide myopic peripheral defocus. Despite WO 2009/129528 A1 indicates the suitability of said lens for spectacles, in particular, the above co-applicant points to a design targeted for a contact lens.

Well known due to market success are in particular Coopervision's contact lenses, the principle of which is, e.g., disclosed in WO 2010/129465 A1. The ophthalmic lens disclosed therein comprises or includes a vision correction region and a myopic defocus region. In an example disclosed in WO 2010/129465 A1 the ophthalmic lens is a contact lens comprises an annular zone with three subrings which surrounds a central zone. While two of the sub-rings belong to the myopic defocus region the third sub-ring, which separates the two sub-rings belonging to the myopic defocus region, belongs to the vision correction region, together with the central zone. The vision correction region and the myopic defocus region define an optic zone of the contact lens. The optic zone is circumscribed by a non-optical peripheral zone which extends from an outer perimeter of the optic zone to a peripheral edge zone of the contact lens. The optic zone comprises or consists of a plurality of concentric rings circumscribing a central circular zone.

The central zone of the contact lens is circular or substantially circular and may have a distance optical power and a diameter greater than 2.0 mm. The diameter of the central zone can be determined by measuring a straight line through the optic axis to opposing perimeter boundaries of the central zone in a two-dimensional front plan view of the contact lens.

Similar designs allegedly being suitable for contact lenses and spectacle lenses are also disclosed in US 2016/054588 A1, US2017/276961 A1 and US 2019/227342 A1 assigned to Johnson & Johnson.

In particular, US 2019/0227342 A1 discloses an ophthalmic lens having a center zone with a negative power for myopic vision correction; and at least one treatment zone surrounding the center zone. The at least one treatment zone having a power profile comprising an ADD power. The at least one treatment zone has a surface shape composing a portion of a generally toroidal shape. The at least one treatment zone is arranged as to form a continuous surface with the center zone. As an example, the portion of the toroidal shape may be derived from a torus (e.g., spheroidal torus), wherein a slice through the surface of the spheroidal torus to generate the portion of the toroidal shape comprises a right circular conical surface with the principal axis of the cone coincident with the axis of rotation about which the torus is generated. The treatment zone may be configured to result in a ring focus. A position of the focal ring may be dependent upon the optical power of the treatment zone.

Optical function of a radially concentric multizone ophthalmic lens that serves at least a spherical correction purpose according to US 2019/0227342 A1 is most generally derived from a front and back surface. One of these surfaces may be spheroidal or ellipsoidal in nature. The other surface typically has a spheroidal or ellipsoidal cap and then one or more curved portions, each of which is the surface of a spheroidal or ellipsoidal frustum (“zone”) that is symmetrically arranged so as to form a continuous surface. The zones may be radially concentric and optically coaxial about a common axis.

Each frustum may be created by sectioning a spheroid or ellipsoid of appropriate size and shape to achieve the desired optical power, perpendicular to the principal axis of such spheroid or ellipsoid. In some cases, a transitional region (e.g., an optically dysfunctional) may be required to allow the individual zones to form a continuous surface. For myopia treatment, some of the zones will generally produce a more positive wavefront derivative than the zone or zones devoted to correct distance vision, where the wavefront derivative is taken with respect to the radial distance from the principal axis (dW/dr). Rays of light parallel to the common axis and passing through the zones will come to a principal focus for each zone, and these foci will be located on the common axis for rotationally symmetric zones. When the ophthalmic lens is used to correct vision and where one or more of the zones have principal foci of different focal length, the image formed at the retina of the eye may come along with ghosting or haloes, leading to degradation of vision.

US 2019/0227342 A1 discloses embodiments having a zone (or replacing a designed zone of the lens) with a surface shape derived from a toroidal shape (e.g., spheroidal torus) or, in the case of replacing multiple zones, from one or more tori. As an example, the portion of the toroidal shape to be utilized may be derived from a torus (e.g., a spheroidal torus), after making a slice in the shape of the surface of a right circular cone through the surface of the spheroidal torus wherein the principal axis of the cone is coincident with the axis of rotation about which the torus is generated. The portion of the torus forming part of the lens surface is so arranged as to form a continuous surface with other zones of the lens or being joined by an optically dysfunctional, transition region to allow the individual zones to form a continuous surface. Other slices (conical or otherwise) than outlined in the document are indicated as being suitable to be used.

Hong Kong Polytechnic University and Hoya recently disclosed a different kind of spectacle lenses following the general approach described in WO 2005/055891 A1. Hoya sells such spectacle lenses under the trademark MyoSmart. The spectacle lenses are known as MSMD (multi segment myopic defocus) lenses. The respective technical concept is known as D.I.M.S. (Defocus Incorporated Multiple Segments) technology. Details are, for example, disclosed on the internet site www.hoyavision.com/en-hk/discover-products/for-spectacle-wearers/special-lenses/myosmart/. Respective spectacle lenses are disclosed in US 2017/131567 A1. The spectacle lenses comprise a central zone providing full correction and a plurality of microlenses/lenslets surrounding the central zone and providing an additional power of e.g., approximately 3.5 D. A similar approach is used in Essilor's Stellest spectacle lenses being described in detail in EP 3 553 594 A1, EP 3 561 578 A1, WO 2019/166653 A1, WO 2019/166654 A1, WO 2019/166655 A1, WO 2019166657 A1, WO 2019/166659 A1 and WO 2019/206569 A1, respectively. The microlenses/lenslets are aspherical and have an optical power in their geometrical center which lies in the range between 2.0 dpt and 7.0 dpt in absolute value, and an optical power in their periphery which lies in the range between 1.5 dpt and 6.0 dpt in absolute value. The refractive optical power provided by the aspherical microlenses/lenslets exceeds the refractive power of the clear central zone by 0.5 dpt or more.

Also WO 2020/014613 A1 assigned to Sightglass Vision Inc. recently disclosed a myopia control spectacle lens that may contain one or more defocus elements, i.e., a myopia control spectacle lens may contain a clear center, free of said defocus elements treating children having, or suspected of having, myopia by having the children wear spectacles with myopia control lenses provides a safe, efficient, and non-invasive method for reducing the progression of juvenile myopia. Exemplarily, the document refers to regions that comprise island-shaped lenses.

WO 2010/075319 A2 also refers to the importance of peripheral retinal image determining myopic eye growth. The document proposes a therapeutic treatment method for preventing, ameliorating, or reversing eye-length-related disorders, the therapeutic treatment method comprising: identifying, in a patient, an eye-length-related disorder; and inducing artificial blurring of the patient's peripheral vision in order to decrease an average spatial frequency of images input to the retina of the eye past a threshold spatial frequency to inhibit further lengthening of the patient's eye. In particular, the document proposes providing the patient with spectacle lenses having a first area including a plurality of first elements selected from the group consisting of: (i) bumps on a surface of the spectacle lens; (ii) depressions on the surface of the spectacle lens; (iii) first translucent inclusions in a spectacle lens material; and (iv) first transparent inclusions in the spectacle lens material, the first transparent inclusions having a refractive index different from that of the spectacle lens material. The elements in general are point-shaped elements having a non-zero point density in a range between 0 and 8 dots per mm.

Improvements of this kind of spectacle lenses are disclosed in WO 2018/026697 A1 and WO 2019/152438 A1, respectively.

In particular, WO 2018/026697 A1 discloses a pair of eyeglasses, comprising: eyeglass frames; and a pair of spectacle lenses mounted in the frames, the spectacle lenses comprising a point pattern distributed across each spectacle lens, the point pattern comprising an array of dots spaced apart by a distance of 1 mm or less, each point having a maximum dimension of 0.3 mm or less.

WO 2020/113212 A1 and a contrast reduction region comprising scattering centers and/or one or more lenslets for reducing image contrast.

WO 2019/152438 A1 discloses a spectacle lens, comprising: a lens material having two opposing curved surfaces; and a scattering region surrounding a clear aperture, wherein the scattering region has a plurality of spaced apart scattering centers sized and shaped to scatter incident light, the scattering centers being arranged in a pattern that includes an irregular variation in spacing between adjacent scattering centers and/or an irregular variation in scattering centers size.

WO 2010/075319 A2, WO 2018/026697 A1, WO 2019/152438 A1 and WO 2020/014613 A1 describe spectacle lenses with artificial peripheral scattering while WO 2020/113212 A1 and WO 2020180817 A1 describe spectacle lenses with a contrast reduction region comprising scattering centers and/or one or more lenslets for reducing image contrast. Introducing artificial peripheral scattering is somewhat in contradiction to the findings described in WO 2005/055891 A1 and WO 2007/092853 A2 with respect to annular diffusing lenses, however, the results of respective trials based on SightGlass Vision's DOT spectacle lenses have been disclosed to be promising.

Each microlens/lenslet of the spectacle lenses described in US 2017/131567 A1 or EP 3 553 594 A1, EP 3 561 578 A1, WO 2019/166653 A1, WO 20191/66654 A1, WO 2019/166655 A1, WO 2019/166657 A1, WO 2019/166659 A1 and WO 2019/206569 A1, respectively, and being described in detail above, must separately be produced. Therefore, there is a need for spectacle lenses which may be produced by a simplified fabrication technology but still providing optical properties resembling those described in the foregoing to control myopia progression.

From US 2019/0227342 A1 contact lenses and spectacle lenses using a torus instead of. microlenses/lenslets for providing a myopic defocus are known. However one very feature disclosed in US 2019/0227342 A1 is that the portion of the torus forming part of the lens surface is so arranged as to form a continuous surface with other zones of the lens or being joined by an optically dysfunctional, transition region to allow the individual zones to form a continuous surface. To achieve the continuity a specific adaption in the design of the surface of the contact lens or spectacle lens is necessary, which means amending the whole surface of the contact lens or spectacle lens as compared to a surface without the torus. In addition, also as specific adaptions in production are necessary. Moreover, in cease of more than one torus the zones between the tori do not contribute in at least retarding myopia progression.

WO 2020/113212 A1 discloses a spectacle lens design including a zone providing a focused image on the fovea that is surrounded by a zone with focusing structures for generating a myopic defocus or by a diffusing zone.

WO 2019/166657 A1, which is regarded as closest state of the art, discloses a spectacle lens design including an aperture that provides a focused image on the fovea and that is surrounded by a zone with focusing structures for generating a myopic defocus. A focusing structure of WO 2019/166657 A1 either provides a ring shaped focal line or a plurality of foci arranged along a ring shaped line. Between the focusing structures that surround the zone providing the focused image there is no means that contributes to stopping or slowing down myopia which means that the zone with focusing structures is not optimally used for stopping or slowing down myopia.

With respect to WO 2019/166657 A1 it is a first objective of the present disclosure to improve the spectacle lens design of WO 2019/166657 A1 so that its effectivity in stopping or slowing down myopia is increased.

It is a second objective of the present disclosure to provide a method of manufacturing a spectacle lens which allows improving the spectacle lens design of WO 2019/166657 A1 so that that its effectivity in stopping or slowing down myopia is increased.

It is a third objective of the present disclosure to make available a computer implemented method of providing a spectacle lens design that allows for providing a spectacle lens design which is compared to the spectacle lens design disclosed in WO 2019/166657 A1 improved in that its effectivity in stopping or slowing down myopia is increased.

The first objective is achieved by spectacle lens designs for a spectacle lens having an aperture, at least two ring-shaped focusing structures, and a ring-shaped diffuser. The second objective is achieved by a method of manufacturing such a spectacle lens, and the third objective is achieved by a computer implemented method of providing such a spectacle lens design for at least retarding myopia progression.

The following definitions are used within the scope of the present description:

Additional Power

In the context of the present specification, the term “additional power” applies to a focal power that is added to the focal power of a spectacle lens, where the focal power of a spectacle lens provides, assisted by accommodation, a focused image on the fovea and the additional power, when added to the focal power of a spectacle lens, provides for a myopic defocus. The additional power must not be confused with the addition power of a progressive addition lens.

Aperture

In the context of the present specification, the term “aperture” applies to a zone of a spectacle lens that is surrounded by one or more ring-shaped structures. In some variants of the aperture, a number of structures may be located within the aperture. Such structures would provide an effect in addition to the focal power provided by the spectacle lens in the area of the aperture. However, the area occupied by the structures within the aperture should not exceed 20% of the whole area of the aperture. In other variants, the aperture is free of any structures so that the aperture only exhibits the focal power provided by the spectacle lens.

As-Worn Position

The as-worn position is the position, including orientation, of the spectacle lenses relative to the eyes and face during wear (DIN ISO 13666:2019, section 3.2.36). The as-worn position is determined by the as-worn pantoscopic angle, the as-worn face form angle and the vertex distance. The as-worn pantoscopic angle is the vertical angle between the horizontal and the perpendicular to a reference line passing through the apex of the grooves of the upper and lower rims of the frame in the vertical plane containing the primary direction (DIN ISO 13666:2019, section 3.2.37), where the primary direction is the direction of the line of sight, usually taken to be the horizontal, to an object at an infinite distance measured with habitual head and body posture when looking straight ahead in unaided vision (DIN ISO 13666:2019, section 3.2.25) and the line of sight is the ray path from the point of interest (i.e., point of fixation) in object space to the centre of the entrance pupil of the eye and its continuation in image space from the centre of the exit pupil to the retinal point of fixation (generally the foveola) (DIN ISO 13666:2019, section 3.2.24). Typical values of the as-worn pantoscopic angle lie in the range between −20 and +30 degree. The as-worn face form angle is the horizontal angle between the primary direction and the perpendicular to a reference line passing through the apex of the grooves of the nasal and temporal rims of the frame in the horizontal plane containing the primary direction (DIN ISO 13666:2019, section 3.2.38). Typical values of the as-worn face form angle lie in the range between −5 and +30 degree. The vertex distance is the horizontal distance between the back surface of the spectacle lens and the apex of the cornea, measured with the eyes in the primary position (DIN ISO 13666:2019, section 3.2.40), where the primary position is the position of the eye when looking in the primary direction (DIN ISO 13666:2019, section 3.2.26). Typical valued of the vertex distance lie in the range between 5 mm and 30 mm. The as-worn position may be an individual as-worn position determined for a specific individual or a generic as-worn position determined for a defined group of wearers.

Central Zone

In the context of the present disclosure, a central zone is a zone of a spectacle lens or a spectacle lens design that is surrounded by a surrounding zone the optical properties of which differ from the surrounded central zone.

Clear Zone

In the context of the present specification, the term “clear zone” applies to a zone of a spectacle lens design or a spectacle lens that provides neither a myopic defocus nor a diffusion in foveal vision when a wearer looks through the clear zone with the spectacle lens being positioned according the specified as-worn position. Furthermore, a clear zone allows for achieving, if necessary assisted by accommodation, a focused image on the fovea. There may be zones of a spectacle lens design or a spectacle lens that do neither provide a myopic defocus nor a diffusion in foveal vision when a wearer looks through the respective zone but show a residual astigmatic error leading to a blurred image. Such a zone is not regarded as a clear zone in the meaning used in the present specification.

Contact Line

In the context of the present specification, the term “contact line” applies to a contact zone between two structures contiguously adjoining each other where the geometry surfaces of the structures is such that it is not continuously differentiable in a direction crossing the contact zone.